PC gamepass subscriber here and yes I do. I'll buy the games that I like from the service on Steam/GOG for the following reasons:
- I like permanence in my PC gaming library.
- While being aware that Microsoft have a financial agreement with them I'm happy to give the developer/publisher money directly for a product I like.
- The windows store is a steaming pile of fresh dog shit so any way to minimise the amount of time I need to spend using it is a plus.
- To show that there is still a market for people who wish to purchase games outright, even if those same games are available on a subscription.
I treat services like Gamepass and Origin Access as "demo" subscription services. I'll try a game and if I like it enough I will buy it from a place that I have confidence in. If I don't like it then no harm done, no money wasted.